package MD5Check;

use strict;
use warnings;
use Digest::MD5;
require Exporter;

our @ISA    = qw(Exporter);
our @EXPORT = qw(init md5init md5check);

=encoding utf8
=head1 NAME

MD5Check -  Use it for init Web files's md5 values of your site(or other dir), and check if it changed!

检查web目录（或者其他重要系统目录）md5值，当目录文件变化提醒。用于文件防篡改。

=head1 VERSION

Version 0.11

=cut

our $VERSION = '0.11';

=head1 SYNOPSIS

    use MD5Check;

## 初始化目录md5值,参数为要监控的目录

    my $mydir=shift;
    print init($mydir);

## 对目录文件进行检查，只需输入之前保存的md5 文件值。

    use MD5Check;
    my $mydir=shift;
    print md5check($mydir);

# oneliner，perl单行程序实现功能。

需要安装该模块，简单通过 cpanm MD5Check 安装。

## 相关实例可以直接使用bin/下的init.pl 和 check.pl 单行执行

    $ perl -MMD5Check -e 'init("/web")' >file
    $ perl -MMD5Check -e 'print md5check(file)'..


=cut

my $DEBUG = 0;

sub md5_sum {

    my ( $file_name, $mode ) = @_;
    my ( $FD, $ctx, $md5 );
    eval {open( $FD, $file_name ) or warn  "Can't open $file_name !";};
   unless($@) { 
    $ctx = Digest::MD5->new;
    binmode($FD) if $mode;
    $ctx->addfile($FD) or warn "$!\n";
    $md5 = $ctx->hexdigest;
   close $FD if $FD; 
   return $md5;
   }
}

sub md5check {
    my $file = shift;
    open( my $fd, '<', $file ) or warn "$file: $!\n";
    my $res .= $file . "\n";
    while (<$fd>) {
        chomp;
        next if /$file/; # ignore the recode file itself
        my ( $name, $sum ) = split /\|\|/;
        print $name,"\n" if $DEBUG;
        print $sum,"\n" if $DEBUG;
        print md5_sum( $name, 1 ),"\n" if $DEBUG;
        $name =~ s/^\#//;
        if ( $sum eq md5_sum( $name, 1 ) ) {
            $res .= "$name OK\n";
        }
        else {
            $res .= "$name FAILED\n";
        }
    }

    close $fd;

    return $res;
}

# 遍历目录计算md5值

sub init {
    # 仅仅用来打印init信息
    my ($fd) = @_;
    my $res;
    if ( -f $fd ) {
        if ( -T $fd ) {

            #print "按照文本模式计算MD5!\n";
           my $md5value = md5_sum( $fd, 0 );
            print "$fd||$md5value\n" ;
        }
        else {
            #print "其他文件，按照bimmod模式计算!\n";
            my $md5value = md5_sum( $fd, 1 );
           print  "$fd||$md5value\n";
        }
    }
    elsif ( -d $fd ) {
        my $file_md5;
        opendir( my $DH, $fd ) or warn "Can't open dir $fd: $!";
        for ( readdir $DH ) {
            my $file = $fd . '/' . $_;
            # 上级目录..，当前目录. 以及连接文件跳过
            next if ( $file =~ m{/.$} || $file =~ m{/..$} || -l $file );
            eval { init($file);};
            if ($@) {
            }
        }
        closedir $DH;
    }
}


sub md5init {

    my ($fd,$outFD) = @_;
    my $res;
    if ( -f $fd ) {
        if ( -T $fd ) {

            #print "按照文本模式进行计算MD5!\n";
           my $md5value = md5_sum( $fd, 0 );
            print $outFD  "$fd||$md5value\n" ;
        }
        else {
            #print "其他文件，按照bimmod模式计算!\n";
            my $md5value = md5_sum( $fd, 1 );
           print $outFD  "$fd||$md5value\n";
        }
    }
    elsif ( -d $fd ) {
        my $file_md5;
        print "Init for all files $fd:\n";
        opendir( my $DH, $fd ) or warn "Can't open dir $fd: $!";
        for ( readdir $DH ) {
            my $file = $fd . '/' . $_;
            # 上级目录..，本目录. 以及连接文件跳过
            next if ( $file =~ m{/.$} || $file =~ m{/..$} || -l $file );
            eval { md5init($file,$outFD);};
            if ($@) {
              print "Some wrong for init $file\n ";
            }
            print "Debug::", $res if $DEBUG;
        }
        closedir $DH;
    }
    return $res;
}

1;
__END__

=head1 DESCRIPTION

MD5Check - Use it for init Web files's md5 values of your site(or other dir), and check if it changed.

MD5Check is not standardized. This module is far from complete.


=head2 IMPLEMENTATION

#Init the web dir md5 values

    use MD5Check;
    my $mydir=shift;
    print  md5init($mydir,$OUT);
=====================
#check files 

    use MD5Check;
    my $mydir=shift;
    print md5check($mydir);

=head1 Git repo

L<https://github.com/bollwarm/MD5Check.git>

=head1 AUTHOR

orange C<< <linzhe@ijz.me> >>, L<http://ijz.me>

=head1 COPYRIGHT AND LICENSE

Copyright (C) 2016 linzhe

This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.


=cut


=head1 AUTHOR

orange, C<< <linzhe at ijz.me> >>

=head1 BUGS

Please report any bugs or feature requests to C<bug-md5check at rt.cpan.org>, or through
the web interface at L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=MD5Check>.  I will be notified, and then you'll
automatically be notified of progress on your bug as I make changes.




=head1 SUPPORT

You can find documentation for this module with the perldoc command.

 perldoc MD5Check


You can also look for information at:

=over 4

=item * RT: CPAN's request tracker (report bugs here)

L<http://rt.cpan.org/NoAuth/Bugs.html?Dist=MD5Check>

=item * AnnoCPAN: Annotated CPAN documentation

L<http://annocpan.org/dist/MD5Check>

=item * CPAN Ratings

L<http://cpanratings.perl.org/d/MD5Check>

=item * Search CPAN

L<http://search.cpan.org/dist/MD5Check/>

=back


# End of MD5Check
